Just use them as they natively come, that would be the best comparison!
16mm without any coil cover
Showerhead with coil cover
That will give the best representation of how much lower you can go with the showerhead.
Just my
I'll do my best , unfortunately with the latest designs all i have is 20mm so that is what i will be testing , my 16mm setup is the og design and i will most likely be retiring that and sticking with the 20mm setups now. I can tell you my og 16mm setup with no coil cover or dish built in works very well. The new designs are proving to be a bit better though. With my Og 16mm 674F seemed to be my sweet spot for both flower & concentrate , now with the coil cover , built in dish around the head and 20mm using both that and the showerhead are allowing me to drop temps , so far at 640F they are working well for both. I'll try for some lower temps and comparisons between the 2 shortly. I'll tell you this though , you can go a bit lower with the 20mm setup over the 16mm and always a 5-10 minute preheat helps greatly. Now i just have to see how the 20mm shower head stacks up against the 20mm with the dish built in.
* Showerhead users , i am using this carb cap and it fits well -
https://stokedct.com/product/karl-termini-stemware-carb-cap-chillum/ , if its to pricey they do make a clear version for $40 , i am sure NewVape will have something soon for all us.
New User's looking for info , Please refer to this picture for the original style parts and click this link for a read about some updates and help :
https://www.newvape.com/vape-essentials/flowerpot-twax-vaporizer/flowerpot-faq , the updates made that are not in this picture are the Showerhead , FlowerPot Coil Cover that can be added to any setup and wrap around style heads that add a dish around your quartz , sic or titanium head you choose that should help spread some heat more evenly , all setups work well imo and you cannot go wrong with any setup you choose.